1. Field of the Invention
The present invention relates to a refrigerator comprising a cabinet forming a food storage space and a door for opening and closing the space.
2. Description of the Related Art
It is well known that direct cooled freezers present the problem of manual defrosting of evaporators, due to the frost build-up during normal operation of the direct cooled freezer.
Manual defrosting of direct cooled freezers can be very time consuming for users. A user must remove all of the frozen goods from the freezer and manually initiate the defrosting routines. This causes the user to schedule this activity carefully in advance, to avoid spoiling the frozen goods during the defrost operation.
The most prevalent alternative technique to manually defrost is related to hot gas defrosting of a freezer evaporator, which allows quick defrosting by hot gas circulation which melts the frost layer. However, this is not an easy operation since the user still must remove all of the frozen goods from the freezer, then make the frost layer melt by the hot gas defrosting, and finally put the goods back in the freezer before they thaw. Another technology is the no-frost refrigerator/freezer where the cold surfaces of the evaporator are located outside of the freezer cavity in a separate space, and cold air is forced by a fan to flow over the evaporator. In this way, the frost layer can be melted using an electric heater and defrost water is discharged out of the compartment by a drain pipe. This technology provides automatic defrosting but consumes more energy.
The automatic defrosting offered by the no-frost freezers has additional disadvantages, such as reduced volume available for the frozen goods. Also, the no-frost freezers draw moisture from the frozen goods, so the user must wrap the goods in plastic or store the goods in boxes to prevent dehydration. Moreover, no-frost freezers are costly and less energy efficient.
Thus, an improvement over the prior art would be to improve defrosting of direct cooled freezers without the disadvantages of present manual defrosting or the disadvantages of automatic defrosting of no-frost freezers.